DE 40 28 656 A1 discloses a method which aims to use permanently calibrated force-measuring balancing machines to identify a convergence with a resonance speed which is too great and a thereby induced distortion in the measurement result. In this case, at least three unbalance measurements are determined at various measuring speeds during the unbalance-measuring run, from which measurements at least two differentials of the unbalance measurements which follow on from one another in terms of speed are formed by an evaluation circuit. If the evaluation circuit finds that the differentials between the neighbouring higher measuring speeds are proportionally greater than those between the neighbouring lower measuring speeds, a resonance step-up is found and signalled.
Furthermore, CN 1 02 175 394 A discloses a method for permanently calibrating a soft-bearing balancing machine, in which the resonant frequency of the oscillatory system comprised of the rotor bearing and measured rotor is calculated with reference to the frequencies and amplitudes of the rotor bearing which are measured during acceleration of the motor, and the influence of the rotor mass on the oscillation amplitude is described by imaging and the influence of the mass and speed of the rotor on the calibration is eliminated.